Here's the thing. Our brains constantly play tricks on us. I'm sure that everyone does remember her having braces... because for whatever reason that's what their brains were feeding them. Some combination of the shit in Jaws' mouth, combined with her looking like a young girl who would have braces. Who knows.
When I was a kid I had a business card that, and this is gonna sound weird, a guy in a gas station in New Mexico gave to my dad on a trip (gas station dude was apparently so taken by this that he had a bunch made to hand out). The idea was to count the vowels on the card. So you counted, and got 12 or whatever. Nope. The actual answer was something like 22. And everyone would say "No I just counted. It's 12." But when they would count again with the number 22 in their heads.... they would get 22. It was a real mind fuck, that has nothing to do with this topic other than that our brains process information pretty weirdly.